System and method for improved reading of data from reflective surfaces of electronic devices

ABSTRACT

Disclosed systems and methods for a data reader operable to capture one or more images from items having a highly, or relatively highly, reflective surface. The data reader includes a controller/processor in operative communication with an imager and an illumination system, where the controller/processor is programmed to selectively operate the imager and the illumination systems to interleave the data reader between a first reading period for reading items having a surface with little or no reflectivity and a second reading period for reading items having a surface with high reflectivity. In some embodiments, the items with highly reflective surfaces may include electronic devices, such as mobile phones.

BACKGROUND

The field of the disclosure relates generally to data reading devices,and particularly, to improved data reading devices for reading data froma reflective surface of electronic devices.

Optical codes, such as barcodes and other machine-readable indicia,appear in a variety of applications. There are a variety of forms, suchas: linear barcodes (e.g., UPC code), 2D codes including stackedbarcodes (e.g., PDF-417 code), and matrix codes (e.g., Datamatrix code,QR code, or Maxicode). There are several types of data readers used forreading these optical codes. The most common types of optical codereaders are laser scanners and imaging readers. A laser scannertypically moves, i.e. scans, a laser light beam across the barcode.Imaging readers are typically used to capture a 2D image of an area,including the optical code or other scene, focused onto a detector arraysuch as charge-coupled devices (CCDs) and complementary metal oxidesemiconductor (CMOS) imagers. With some such imaging readers, it may beadvantageous to provide a source of illumination that illuminates theoptical code or other scene being imaged, to provide the required signalresponse in the imaging device. Such a source of illumination can reduceexposure time, thereby improving imager performance, especially in lowambient light conditions and when imaging moving items.

Typically, in a grocery or retail establishment, optical codes are oftenprinted directly on items or printed on a sticker that is thereafteraffixed to the item. These optical codes are usually printed or locatedon surfaces with little or no reflectivity so that illumination from adata reading device is not reflected back toward the data readingdevice, which may render the image obtained by the data reader difficultto process.

Businesses have begun sending optical codes to customers who displaysuch optical codes on a portable electronic device, such as a mobiletelephone or cell phone, personal digital assistant, palm, tablet, orlaptop computer, or other suitable device having an electronic display,such as a liquid crystal display (LCD). For example, an airlinepassenger may display an optical code on a portable electronic devicefor an airline employee to read using a data reader as verification ofthe passenger's ticket. Or, a customer in a store may display an opticalcode on a portable electronic device for a cashier to read using a datareader to redeem a coupon. Optical codes are also included on otheritems having highly, or relatively highly, reflective surfaces, forexample, but not limited to, identification (ID) cards, aluminum cans,and objects in plastic packaging.

The present inventors have recognized that optical codes presented on,or under, a highly, or relatively highly, reflective surface aretypically difficult to decode using general-purpose data readers. Forexample, the present inventors have recognized that general-purpose datareaders commonly use artificial illumination to illuminate an objectbearing an optical code to create an image of the optical code havingsufficient contrast for decoding the optical code. The present inventorshave also recognized that highly, or relatively highly, reflectivesurfaces bearing optical codes commonly reflect a large amount of suchartificial illumination resulting in a saturated, or partiallysaturated, image that does not have sufficient contrast for decoding theoptical code because all, or portions, of the image appear light, orwhite. However, simply eliminating the artificial illumination is not apracticable solution since the data reader may not otherwise havesufficient illumination to read optical labels from non-reflectiveitems, which would likely be the most common use of the data reader.

Other general-purpose data readers may be capable of detecting thepresence of an electronic device or other reflective surface bydetecting the amount of light reflected toward the data reader. In somesystems, the data reader may attempt to switch from a primary datareading mode (e.g., reading data from items having non-reflectivesurfaces or surfaces with relatively low reflectivity) to a secondaryreading mode (e.g., reading data from items having highly reflectivesurfaces) in response to detecting the electronic device. However, manyexisting data readers have difficulty reliably detecting the presence ofan electronic device. In such cases, the data reader may improperlyswitch to the secondary reading mode, thereby being unable to readnormal optical codes on non-reflective surfaces, or may fail to properlyswitch over when presented with an electronic device, thereby beingunable to read data from highly-reflective surfaces of the electronicdevice.

Still other data readers attempt to divide the imager between theprimary and secondary reading modes, dedicating a specific percentage ofthe imager exclusively to each reading mode. Accordingly, the imagerincludes an area specifically dedicated to detecting an electronicdevice and reading data therefrom, and an area specifically dedicated toreading data from non-reflective surfaces. However, the presentinventors have recognized that a disadvantage of this configuration isthat the data reader dedicates significant resources for reading datafrom electronic devices regardless of whether such a device is presentor not, which detrimentally affects overall performance of the datareader by reducing resources that may be used for reading data fromnon-reflective surfaces, which as noted previously, is likely the mostcommon use of the data reader.

Thus, the present inventors have identified a need for a general-purposedata reader that has improved versatility in handling reading of opticalcodes appearing on (or behind) highly, or relatively highly, reflectivesurfaces, as well as reading optical codes appearing on surfaces have noor little reflectivity.

SUMMARY

Methods and systems are disclosed for improved reading of optical codeson highly reflective surfaces, such as a display on a mobile phone orother electronic device.

In one example system/method, the data reader includes an imager havinga first portion for reading optical codes from electronic devices orfrom other highly reflective surfaces, and a second portion dedicated toreading optical codes from non-reflective surfaces or surface havinglittle reflectivity. The data reader includes an illumination module anda processor designed to control the illumination output during thereading process, where the processor controls the output depending onwhether the data reader is obtaining data from a highly reflectivesurface or from a non-reflective surface (or surface with lowreflectivity). In some embodiments, the processor interleaves the firstportion of the imager to alternate between reading periods for highlyreflective and non-reflective surfaces. By interleaving the firstportion of the imager, the data reader may be able to quickly andefficiently read data from a variety of surfaces while also minimizingreflectivity issues.

Additional aspects and advantages will be apparent from the followingdetailed description of example embodiments, which proceeds withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically illustrates a data reader reading an optical codedisplayed on a display screen of an electronic device.

FIG. 2 is a diagrammatic view of a data reader according to an exampleembodiment.

FIG. 3 is a diagrammatic top view of the data reader of FIG. 2.

FIG. 4 is a diagrammatic view illustrating an example of imager viewallocation for the data reader of FIG. 2.

FIG. 5 is a diagrammatic view of the data reader of FIG. 2, illustratingan example reading process from a reflective surface of an electronicdisplay.

FIG. 6 is a diagrammatic view of the data reader of FIG. 2, illustratingan example reading process from a non-reflective surface or othersurface with low reflectivity.

FIGS. 7-8 are diagrams illustrating relative timing of imager frameexposure and illumination pulses of the data reader of FIG. 2.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

With reference to the drawings, this section describes particularembodiments and their detailed construction and operation. Theembodiments described herein are set forth by way of illustration onlyand not limitation. The described features, structures, characteristics,and methods of operation may be combined in any suitable manner in oneor more embodiments. In view of the disclosure herein, those skilled inthe art will recognize that the various embodiments can be practicedwithout one or more of the specific details or with other methods,components, materials, or the like. For the sake of clarity andconciseness, certain aspects of components or steps of certainembodiments are presented without undue detail where such detail wouldbe apparent to those skilled in the art in light of the teachings hereinand/or where such detail would obfuscate an understanding of morepertinent aspects of the embodiments.

In the following description of the figures and any example embodiments,the system may be referred to in conjunction with use at a retailestablishment. It should be understood that such use is merely oneexample use for such a system. Other uses for a system with thecharacteristics and features described herein may be implemented, forexample, in an industrial location such as a parcel distribution (e.g.,postal) station or for processing inventory, as well as other suitableuses that may involve reading optical codes from electronic devices orother reflective surfaces. In addition, for convenience, certainembodiments may refer to the data reader operable for capturing opticalcodes from a mobile or cellular phone. It should be understood that thisis merely one example embodiment and use of the system with the featuresand functionalities described herein. The system may be used to captureoptical codes from any suitable device or product having a reflectivesurface.

For convenience, the following description may at times refer to thedata reader having a normal label reading mode or period and anelectronic device reading mode or period. References to the normal labelreading mode or period may refer to instances where the data reader isused to obtain images from items having surfaces with little or noreflectivity such that specular reflection issues do not meaningfullyinterfere with an ability of the data reader to capture a decodableimage (i.e., reflected illumination does not saturate the imager).References to the electronic device reading mode or period may refer toinstances where the data reader is used to obtain images from itemshaving surfaces with high reflectivity, and in some casesself-illuminating displays, such as electronic devices with LCD displayscreens, where reflected illumination may saturate the imager andinterfere with an ability of the data reader to capture a decodableimage from an electronic device. These references are meant to establisha frame of reference for convenience purposes and are not intended tootherwise limit the disclosure.

Collectively, FIGS. 1-8 illustrate embodiments of a data reader 10 thatmay be used in a typical checkout process, such as in a retail store orsupermarket, to read optical codes or other data from typical groceryitems and from electronic devices regardless of the reflectivitycharacteristics of the surface to which the optical label or data isaffixed or otherwise presented on. Since many customers nowadays usetheir mobile phones or other electronic devices to carry coupons,loyalty cards, identification cards, credit cards, or other items thatmay be part of a typical checkout transaction, it is advantageous for asingle data reader 10 to have the capability of reading data from avariety of sources, including from screens and electronic devices thatmay have highly reflective surfaces.

For example, with reference to FIG. 1, in one embodiment, the datareader 10 is capable of easily and efficiently reading the optical labelor other data 12 from a display screen 14 of an electronic device 16,while minimizing or entirely avoiding specular reflection issues thatmay arise due to the high reflectivity of an exterior surface 18 of thedisplay screen 14. The data reader 10 is also easily able to read anoptical label or barcode (not shown) affixed to a typical grocery item,such as a cereal box or the like, where specular reflection may not bean issue because the optical label is typically printed on or otherwiseaffixed on a surface with little or no reflectivity. As is explained inmore detail below, the data reader 10 may be used during a typicalcheckout process to read optical codes or other data from normal items50 (see FIG. 6) and also from an electronic device 16 without requiringthe operator to cycle between different readers or manually togglebetween different reading modes of a data reader. Additional details ofthese and other embodiments of the data reader 10 are described hereinwith reference to the figures.

FIG. 1 is a diagrammatic view of a data reader 10 in accordance with oneembodiment shown reading a barcode 12 displayed on the display screen 14of a pda (personal digital assistant) or cell phone 16 (a smartphonebeing illustrated). The data reader 10 is illustrated as a Magellan3300HSi model bar code reader available from Datalogic of Eugene Oreg.(U.S.A.), but any suitable imaging reader may be employed. The datareader 10 is schematically depicted as a horizontal single plane scannersuitable for reading optical codes, symbols, or other items. The datareader 10 is illustrated, by way of example, as a single window reader,but in other embodiments may be a presentation scanner, a multi-windowreader, or may be arranged in any one of a variety of suitableconfigurations. The reader 10 may be configured as a fixed unit(mountable to a support surface or free standing on a horizontalsurface) or a handheld unit. The reader 10 may alternately be configuredas a combined handheld/fixed unit, e.g., one that may rest/beself-supporting upon a horizontal surface but be grasped by the user andmoved to aim toward an item to be read.

FIGS. 2 and 3 are diagrams illustrating elements of the data reader 10inside a housing 20 according to one embodiment. The data reader 10includes an elongated window 22 and an illumination system comprisingone or more illumination sources 24, 26 (illustrated in FIG. 3 as a rowof group LEDs) for illuminating the read region 28 in front of thewindow 22. The data reader 10 includes an imager 32, which is shownmounted on a printed circuit board 42 disposed adjacent a bottom of thereader housing 20. The imager 32 may be a complementary metal oxidesemiconductor (CMOS) imager, a semiconductor charge-coupled device (CCD)imager, or comprise other suitable imaging technology. In oneembodiment, the CMOS imager may comprise an active-pixel imaging sensorwith a global shutter, such as a model EV76C570 sensor sold by e2Vtechnologies plc of Chelmsford, England or may operate on a rollingbasis.

The data reader 10 may acquire an image of the read region 28 usinganyone of a variety of mirror configurations. In one embodiment, animage of the read region 28 may be divided into a first portion 28 a anda second portion 28 b, each of which may be reflected off a series ofmirrors (or other optical components) toward focusing optics 30, whichin turn focuses the portions 28 a, 28 b onto the imager 32. For example,the first portion 28 a may be reflected sidewardly by a first mirror 34toward a second mirror 36, which directs the first portion 28 a towardthe focusing optics 30. Similarly, the second portion 28 b may bereflected sidewardly by a third mirror 38 toward a fourth mirror 40,which directs the second portion 28 b toward the focusing optics 30. Inother embodiments, the mirrors may be arranged in a differentconfiguration suitable to provide an image of the read region 28 ontothe imager 32.

Preferably, the mirrors are arranged so that at least one portion (e.g.,28 c in FIG. 2) of one of the fields-of-view (e.g., view 28 b in FIG. 2)is directed at an angle α that is perpendicular or substantially dose toperpendicular (for example, ranging from 70° to 90°) with reference tothe window 22, and another portion (e.g., 28 d in FIG. 2) of the view 28b is directed at an angle β ranging from 60° to 90° to provide optimalviewing conditions to allow the data reader 10 to acquire an image whenan electronic device 16 having a highly reflective screen surface ispresented.

The imager 32, alone or together with logic components such as a complexprogrammable logic device (CPLD) or a field-programmable gate array(FPGA), is coupled to a controller or processor 44, which, among otherfunctions, is preferably programmed to control operating parameters ofthe data reader 10 as discussed in further detail below. Processor 44 isalso preferably programmed to read and decode optical codes or othersymbols or imaged items. The processor 44 may comprise any suitabledigital processor, such as a low-power DSP core or ARM core processor.In some embodiments, processor 44 comprises an ARM9 processorAT91SAM9G20 sold by Atmel of San Jose, Calif., USA, or OMAP processorsold by Texas Instruments of Dallas, Tek, USA or an i.MX1 seriesprocessor (such as the MC9328MX1 processor) sold by FreescaleSemiconductor, Inc, of Austin, Tex., USA. Alternately, multipleprocessors or sub-processors or other types of processor electronicssuch as comparators or other specific function circuits may be usedalone or in combination. For the purposes of this description, the termprocessor is meant to include any of these combinations.

In one embodiment, the processor 44 and on-board memory 46 are mountedon PCB 42 adjacent the imager 32, and are operable for controllingoperation of the imager 32 and other reader components. The memory 46may be flash memory, random access memory, or other suitable memory incommunication with the processor 44. In some embodiments, memory 46 maybe integrated with processor 44.

As mentioned previously, the data reader 10 includes illuminationsources 24, 26 to illuminate the optical code on the item presented tothe data reader 10. In one embodiment, the illumination sources 24, 26comprise a collection of LEDs, for example, infrared or visible spectrumLEDs, but may alternatively comprise another suitable light source, suchas a lamp or laser diode. The illumination sources 24, 26 may be coupledto and controlled by the processor 44 or may be remotely mounted andpowered.

With reference to FIG. 4, in one embodiment, the imager 32 may be a twomegapixel imager array that is divided into three views, labeled Views1, 2, and 3. In this configuration, Views 2 and 3 may be dedicated fornormal label reading of items 50 (see FIG. 3) having little or nospecular reflection issues (e.g., items with little or no surfacereflectivity) for every frame. As noted previously, in a typicalcheckout process, most of the items (e.g., grocery items) will likelyhave no specular reflection issues. Accordingly, in one embodiment, alarger share of the imager array 32 (e.g., approximately ⅔ of theimager) may be dedicated specifically for capturing images of theseitems 50. To accommodate data reading from electronic device 16 or othersurfaces having high reflectivity, View 1 may be interleaved toalternate View 1 between normal label data reading (i.e., reading ofitems 50 with little or no specular reflection issues) and electronicdevice reading mode (i.e., reading of items 16 and surfaces with highreflectivity). As is described in further detail below with particularreference to FIGS. 5-8, the processor 44 may control theactivation/pulsing frequency of the illumination sources 24, 26 andimager exposure timing to allow the data reader 10 to automaticallytransition between the normal label reading mode and the electronicdevice reading mode to obtain data from a variety of items havingdifferent surface reflectivity.

FIG. 5 is a diagrammatic view of the data reader 10 illustrating anexample electronic device reading scenario for reading data from thereflective surface 18 of the self-illuminating display screen 14 of theelectronic device 16. FIG. 6 is a diagrammatic view of the data reader10 illustrating an example scenario where the data reader 10 is capableof reading optical codes from an item 50 having a non-reflective surfaceor surface with low reflectivity when the data reader 10 is in theelectronic device reading mode. While the data reader 10 has beendescribed previously as capable of operating in both the electronicdevice reading mode and a normal label reading mode, the processor 44 iscapable of controlling illumination sources 24, 26 and exposure times ofthe imager 32 so that the data reader 10 is not only capable to capturedata from electronic devices during the electronic device reading mode,but is also operable to capture data from normal items 50 that do nothave highly reflective surfaces during the same electronic devicereading mode. For example, when illumination source 24, 26 areactivated, Views 1, 2, and 3 are optimized to read normal labels. Whenonly one of the illumination sources (e.g., illumination source 24 inFIG. 5) is activated, Views 2 and 3 are optimized for normal labelreading, and View 1 is optimized for cell phone reading as shown in FIG.5. FIGS. 5 and 6 illustrate an embodiment of how this process operates.Additional details regarding specific control protocols by the processor44 for controlling the illumination sources 24, 26 and exposure time ofthe imager 32 are further described with reference to FIGS. 7-8 below.

FIG. 5 is a diagrammatic view of the data reader 10 illustrating anexample reading scenario for reading data from the reflective surface 18of the display screen 14 of the electronic device 16. With particularreference to FIG. 5, the illumination sources 24 of the data reader 10are preferably arranged so that when the illumination sources 24 areactivated, a first travel path 48 of the illumination generated from theillumination sources 24 is generally directed at an acute angle θrelative to the window 22 so that at least a substantial portion,preferably the entirety, of the illumination generated from theillumination sources 24 is reflected off the self-illuminating displayscreen 14 of the electronic device 16 and travels along a second travelpath 50 away from the read region 28 so that the illumination is notdetected by the imager 32. Without the additional illumination from theillumination source 24 (which may otherwise saturate the imager 32), theimager 32 is able to obtain an image of the optical code 12 from thedisplay screen 14 using the backlight illumination generated by theelectronic device 16. In this embodiment, the illumination source 26 isnot activated during the exposure time of the imager 32 because most ofthe illumination from illumination source 26 would be reflected backinto the imager 32 and impair the obtained image.

It should be understood that the acute angle θ may depend on variousfactors, such as the number and arrangement of illumination sources 24,and a distance of the illumination sources 24 to the window 22. Inaddition, different light sources may have different light dispersionfields depending on various factors of the light source. For example, inone embodiment, the dispersion field may be conically shaped. Assumingthe dispersion field of the illumination sources 24 is conically shaped,the acute angle θ may be measured based on a center line of the conicaldispersion field.

FIG. 6 is a diagrammatic view of the data reader 10 illustrating anexample of the data reader 10 obtaining an image from an item 50 havinga non-reflective surface or other surface with low reflectivity when thedata reader 10 is in the electronic device reading mode. In the samearrangement as described in FIG. 5, the illumination from illuminationsource 24 travels along the same travel path 48, but because ofdifferent specular reflection characteristics from the item 50 with anon-reflective surface 52, at least a portion of the illuminationtravels along a third travel path 54 and is ultimately detected by theimager 32. Depending on the reflectivity of the surface 52, portions ofthe illuminating traveling along travel paths 56, 58, 60 may or may notalso be detected by the imager 32. The reflected light from thenon-reflective surface 52 provides sufficient light for the imager 32 toobtain a decodable image of the optical label on the item 50. In someembodiments, to avoid direct reflection of illumination from the window22 for illumination source 26, the illumination source 26 and/or thewindow 22 may be positioned further away from the imager 32.

The reading scenario illustrated in FIGS. 5 and 6 illustrate oneembodiment for controlling the illumination sources 24, 26 and exposuretime of the imager 32 during a data reading operation, which includesreading data from an LCD screen. In other embodiments, the processor 44may control the specific activation of the illumination sources 24, 26and the exposure time to allow the imager 32 to obtain images of theoptical codes or other data present in the read region 28 without regardto the surface reflectivity of the item and without having the operatormanually toggle between reading modes or periods of the data reader 10.For example, as is described in further detail in FIGS. 7 and 8, duringa normal label reading mode, both the illumination sources 24, 26 may beactivated during the exposure time of the imager 32 to providesufficient illumination for the read region 28 so that the imager 32obtains an adequately illuminated image of the optical code on the item50.

With collective reference to FIGS. 7-8, the following sections provideadditional details relating to control parameters of the processor 44for controlling illumination and exposure characteristics of the datareader 10 to allow the data reader 10 to seamlessly transition between anormal reading mode (such as reading optical codes from stickers orother surfaces with no reflectivity) and an electronic device readingmode for reading optical labels from electronic devices. As mentionedpreviously, the processor 44 is operable to control the illumination andexposure times of the data reader 10 to ensure that the illumination andexposure is proper to allow the data reader 10 to capture images from ahighly reflective surface, such as electronic device 16, without havingthe imager 32 become saturated with illumination reflected from themobile device 16, while also allowing the data reader 10 to properlyilluminate optical labels or other data on surfaces with little or noreflectivity to ensure that sufficient illumination is provided toobtain a decodable image. In addition, as mentioned previously withrelation to FIG. 4, certain views or sections of the imager array 32 maybe specifically dedicated for a normal reading mode, and other views orsections of the imager 32 may be interleaved between the normal readingmode and an electronic device reading mode.

FIGS. 7 and 8 are diagrams illustrating relative timing of imager frameexposure and illumination control for the data reader 10 of FIG. 2 inaccordance with one embodiment. With particular reference to FIG. 7, attime T₁, the processor 44 activates both the illumination sources 24, 26to direct light outwardly from the window 22 and illuminate the readregion 28. The processor 44 activates the illumination sources 24, 26 ata desired pulse rate and sets an exposure time for the imager 32substantially equal to the pulse rate so that both illumination sources24, 26 are active during the full exposure time. Turning back to FIG. 2,when illumination source 24 is activated, the illumination travelsgenerally in a direction of the travel path 48 and at an angle θrelative to the window 22. When illumination source 26 is activated, theillumination travels generally in a direction of a travel path 62 toilluminate the read region 28. Since at least a portion of theillumination generated from the illumination source 26 travels outwardlyand generally perpendicularly to the window 22, a substantial portion ofthe illumination from illumination source 26 may be reflected backtoward the imager 32 if an item with a highly reflective surface ispresent at the read region 28. Accordingly, activating both illuminationsources 24, 26 may be useful for items having little or no reflectivityso that the imager 32 is able to capture a proper image without beingsaturated from reflected illumination. However, having both illuminationsources 24, 26 activated for electronic devices would likely saturatethe imager 32 due to specular reflection issues as discussed previously.

Turning back to FIG. 7, at time T₁, when both illumination sources 24,26 are activated during the exposure time of the imager 26, the datareader 10 is in a normal label reading mode or period, where Views 2 and3 (see FIG. 4) of the imager 32 capture an image from items 50 havinglittle or no reflectivity.

At time T₂, for View 1, the processor 44 activates both illuminationsources 24, 26 and sets an exposure time equal to the pulse rate of theillumination sources 24, 26 in a similar fashion as during T₁. Asmentioned previously, View 1 is interleaved between a normal datareading mode or period (when both illumination sources 24, 26 areactivated) and an electronic device reading mode or period (when onlyillumination source 24 is activated). At time T₂, the processor 44 isoperating the illumination sources 24, 26 and setting the exposure timeto operate the data reader 10 in a normal reading mode or period forView 1.

At time T₃, the processor 44 again activates both illumination sources24, 26 and sets an exposure time equal to the pulse rate of theillumination sources 24, 26 in a similar fashion as during T₁. Duringtime T₃, the data reader 10 continues operating in a normal labelreading mode or period.

At time T₄, the data reader 10 switches to an electronic device readingmode or period. During time T₄, the processor 44 controls illuminationsources 24, 26 so that illumination source 24 is activated during theexposure time while illumination source 26 is not activated. In thisconfiguration, View 1 captures an image from the electronic device 16when it is present in the read region 28. Because the illuminationsource 26 is not active during the exposure time, the illumination fromillumination source 26 does not saturate the image obtained by theimager 32 in View 1. As was described previously with respect to FIGS. 5and 6, when the data reader 10 operates in an electronic device readingmode or period, the illumination from illumination source 24 is mostly(if not entirely) reflected away from the imager 32 due to the angle θat which the illumination source 24 is directed toward the reflectivesurface 18 of the electronic device 16. Accordingly, the imager 32 isable to capture a properly illuminated image (using ambient light andillumination from the backlit display screen of the electronic device16) while avoiding light saturation issues since little or noillumination is reflected back into the imager 32 from illuminationsource 24 and illumination source 26 is inactive during time T₄.Moreover, as described with reference to FIG. 6, when a normal item 50is presented to the data reader 10 during time T₄, a sufficient amountof illumination from illumination source 24 is reflected back toward theimager 32 to allow the data reader 10 to capture an image of the normalitem 50 when the data reader 10 is optimized for reading data from anelectronic device. Accordingly, the control of the illumination source24, 26 allows the data reader 10 to operate to read normal items 50 evenwhen specifically configured to read an optical label 12 from anelectronic device 16.

In some embodiments, as illustrated in FIG. 7, the exposure time duringtime T₄ may be lengthened (as compared to the exposure time during thenormal item reading mode) to provide sufficient time for the imager 32to properly capture an image of the optical code 12 from the electronicdevice 16. In some embodiments, the illumination source 24 may beactivated by the processor 44 for only a portion of the exposure time,where the ambient illumination from the electronic device 16 may alsoserve to sufficiently illuminate the read region 28 without the need foradditional illumination from the data reader 10.

The same process described during times T₁ through T₄ may be repeatedagain at times T₅ through T₈ (and so on) in a similar fashion tointerleave the data reader 10 between a normal item reading mode and anelectronic device reading mode.

It should be understood that the scenario described with reference toFIG. 7 is only one embodiment. In other embodiments, the processor 44may be programmed to operate at any desired interleaving ratio for View1. For example, as described, the processor 44 interleaves View 1between normal item reading mode and an electronic device reading modein a 1:1 ratio, that is, View 1 alternates between the normal itemreading mode and the electronic device reading mode. For typicalcheckout processes, this interleaving ratio may be suitable since most,if not all, of the items 50 likely will have no specular reflectionissues. However, in other embodiments where the data reader 10 mayregularly or primarily read data from electronic devices 16, theinterleaving ratio may be greater such that View 1 is dedicated forelectronic device reading more often. Conversely, where the data reader10 does not often read from electronic devices, then the interleavingratio may be smaller such that View 1 operates in an electronic devicereading mode once every three or four cycles, for example.

In other embodiments, the processor 44 may operate and control theillumination sources 24, 26 and the exposure times in a different mannerto effectively alternate between the normal reading and electronicdevice reading modes. In one embodiment, the processor 44 may operate ina multiple integration mode with a long exposure time and cycling theillumination sources 24, 26 independently from one another during theexposure time.

For example, with reference to FIG. 8, at time T₁, the processor 44 mayactivate illumination source 26 during a first portion of the exposuretime (while illumination source 24 is deactivated), and thereafteractivate illumination source 24 (while illumination source 26 isdeactivated) during a second portion of the exposure time. In thisarrangement, the captured frame of the read region 28 corresponds toViews 2 and 3 of the imager 32. The same cycling of illumination sources24, 26 may be run at time T₂ and T₃, with the captured frame at time T₂corresponding to View 1 of the imager 32 and the captured frame at timeT₃ corresponding to Views 2 and 3 of the imager 32. At all three timesT₁, T₂, and T₃, the data reader 10 is operating in a normal item readingmode to read optical labels or other data from items 50 with little orno surface reflectivity.

At time T₄, the processor 44 alternates to the electronic device readingmode. In this arrangement, the processor 44 activates illuminationsource 24 during a first portion of the exposure time, and thereafterdeactivates illumination source 24 during a second portion of theexposure time. During time T₄, the Illumination source 26 is notactivated at any point during the exposure time of the imager 32 tominimize or avoid reflected illumination into the imager 32 fromillumination source 26. As described previously and illustrated in FIG.5, the illumination from illumination source 24 is substantially (if notentirely) reflected away from the imager 32 when an electronic device 16is present in the read region 28. The same process described duringtimes T₁ through T₄ may be repeated again at times T₅ through T₉ in asimilar fashion to cycle the data reader 10 between a normal itemreading mode and an electronic device reading mode.

It should be understood that the scenario described with reference toFIG. 8 is only one embodiment. In other embodiments, the processor 44may be programmed to operate at any desired interleaving ratio for View1. For example, as described, the processor 44 interleaves View 1between normal item reading mode and an electronic device reading modein a 1:1 ratio, that is, View 1 alternates between the normal itemreading mode and the electronic device reading mode. For typicalcheckout processes, this interleaving ratio may be suitable where manyof the items 50 may not have specular reflection issues. However, inother embodiments where the data reader 10 may regularly or primarilyread data from electronic devices, such as electronic device 16, theratio may be greater such that View 1 is more often dedicated forelectronic device reading. Conversely, where the data reader 10 does notoften read from electronic devices, then the interleaving ratio may besmaller such that View 1 operates in an electronic device reading modeonce every three or four cycles, for example.

In other embodiments, the processor may be programmed to pulse one ormore of the illumination sources to avoid or minimize the perception ofillumination flicker by a user or bystander while implementing methodsfor reading optical codes presented on electronic display screens orother highly reflective surfaces. Additional details relating to exampleembodiments are described in U.S. Pat. No. 9,122,939, the disclosure ofwhich is incorporated by reference herein in its entirety.

While certain preferred systems and methods have been shown anddescribed, it will be apparent to one skilled in the art thatmodifications, alternatives and variations are possible withoutdeparting from the inventive concepts set forth herein. Therefore, theinvention is intended to embrace all such modifications, alternativesand variations.

The invention claimed is:
 1. A system for data reading comprising: awindow; an imager for capturing an image of an item bearing an opticalcode, the imager including an imager array divided into a first portionand a non-overlapping second portion; an illumination system forilluminating the item, the illumination system including a firstillumination source and a second illumination source, each of whichdirect light outwardly through the window and into a read region; and acontroller in operative communication with the imager and theillumination system, wherein the controller is programmed to operate theimager and the illumination system during a first reading frame at afirst time period and during a second reading frame at a subsequentsecond time period, wherein during the first time period for the firstreading frame, the controller is programmed to activate both the firstand second illumination sources during a first exposure period of theimager, the controller operating the imager to capture a first image ofa first optical code when a first item is present in the read region,wherein the first portion of the imager is exposed during the firstexposure period to capture the first image on the first portion of theimager; and wherein during the second time period for the second readingframe, the controller is programmed to activate the first illuminationsource during a second exposure period of the imager, and deactivate thesecond illumination source during the second exposure period, thecontroller operating the imager to capture a second image of a secondoptical code when a second item is present in the read region, whereinthe second portion of the imager is exposed during the second exposureperiod to capture the second image on the second portion of the imager.2. The system of claim 1, where the first illumination source isoriented such that illumination generated from the first illuminationsource is directed toward the window at an acute angle relative to thewindow, and wherein when the second item is a reflective display of anelectronic device, the illumination generated from the illuminationsource is reflected off the reflective display such that the imager doesnot detect the illumination from the first illumination source.
 3. Thesystem of claim 2, wherein when the item does not have a reflectivedisplay, the first illumination source is reflected back toward theimager.
 4. The system of claim 1, wherein the processor is furtherprogrammed to interleave between the first reading period and the secondreading period to capture images of items on the first portion of theimager.
 5. The system of claim 4, wherein the processor is furtherconfigured to operate the data reader in the first reading period tocapture images of items on the second portion of the imager.
 6. Thesystem of claim 4, wherein the processor is configured to interleavebetween the first and second reading periods at an interleaving ratio of1:1.
 7. The system of claim 1, wherein during the first reading period,the processor is programmed to pulse the first and second illuminationsources substantially simultaneously at a pulse rate at least equal tothe first exposure period of the imager.
 8. The system of claim 1,wherein during the second reading period, the processor is programmed topulse the first illumination source at a pulse rate at least equal tothe first exposure period of the imager.
 9. The system of claim 1,wherein during the first reading period, the processor is programmed toactivate the first illumination source and then the second illuminationsource in sequence during the first exposure period of the imager.
 10. Amethod for data reading using a data reader having a window, an imagerfor capturing an image of an item, the imager including an imager arraydivided into a first portion and a non-overlapping second portion, andan illumination system including a first illumination source and asecond illumination source, the method comprising the steps of: in afirst reading frame at a first time period, activating, via a processor,the first and second illumination sources during a first exposure periodof the imager to direct light outwardly from the window and into a readregion; exposing, via the processor, the first portion of the imagerduring the first exposure period; if a first item is present in the readregion, capturing, via the imager, a first image of the first item onthe first portion of the imager during the first exposure period; and ina second reading frame at a second time period subsequent to the firsttime period, activating, via a processor, the first illumination sourcesduring the second exposure period to direct light outwardly from thewindow and into a read region; deactivating, via the processor, thesecond illumination sources during the second exposure period; exposing,via the processor, the second portion during the second exposure period;and if a second item is present in the read region, capturing, via theimager, a second image of the second item on the second portion of theimager during the second exposure period.
 11. The method of claim 10,further comprising interleaving, via the processor, between the firstreading period and the second reading period to capture images of itemson the first portion of the imager.
 12. The method of claim 11, furthercomprising operating, via the processor, the data reader in the firstreading period to capture images of items on the second portion of theimager.
 13. The method of claim 12, further comprising interleaving, viathe processor, between the first and second reading period at aninterleaving ratio of 1:1.
 14. The method of claim 10, furthercomprising pulsing, via the processor, the first and second illuminationsources substantially simultaneously at a pulse rate at least equal tothe first exposure period of the imager during the first reading period.15. The method of claim 10, further comprising pulsing, via theprocessor, the first illumination source at a pulse rate at least equalto the first exposure period of the imager during the second readingperiod.
 16. The method of claim 10, further comprising activating, viathe processor, the first illumination source and then the secondillumination source in sequence during the first exposure period of theimager during the first reading period.
 17. A system for data readingcomprising: a window; an imager for capturing an image of an itembearing an optical code; an illumination system for illuminating theitem, the illumination system including a first illumination source anda second illumination source, each of which direct light outwardlythrough the window and into a read region, where the first illuminationsource is oriented such that illumination generated from the firstillumination source is directed toward the window at an acute anglerelative to the window, and wherein when the second item is a reflectivedisplay of an electronic device, the illumination generated from theillumination source is reflected off the reflective display such thatthe imager does not detect the illumination from the first illuminationsource; and a controller in operative communication with the imager andthe illumination system, wherein the controller is programmed to operatethe imager and the illumination system during a first reading period anda different second reading period, wherein during the first readingperiod, the controller is programmed to activate both the first andsecond illumination sources during a first exposure period of theimager, the controller operating the imager to capture a first image ofa first optical code when a first item is present in the read region;and wherein during the second reading period, the controller isprogrammed to activate the first illumination source during a secondexposure period of the imager, and deactivate the second illuminationsource during the second exposure period, the controller operating theimager to capture a second image of a second optical code when a seconditem is present in the read region.
 18. The system of claim 17, whereinthe imager is an imager array divided into a first portion and anon-overlapping second portion, and wherein the processor is furtherprogrammed to interleave between the first reading period and the secondreading period to capture images of items on the first portion of theimager.
 19. The system of claim 18, wherein the processor is furtherconfigured to operate the data reader in the first reading period tocapture images of items on the second portion of the imager.
 20. Thesystem of claim 18, wherein the processor is configured to interleavebetween the first and second reading periods at an interleaving ratio of1:1.